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What Everyone Needs to Know About the Truma Combi

We’ve all experienced colder-than-normal nights in our RVs. Perhaps it was an October evening in the North Carolina mountains when temperatures dipped into the 30s. Or perhaps it was an early April morning in Zion National Park when you woke up to see your breath. One product that is making its way to north America from Europe is offering an excellent way to heat a rig, one that’s sustainable and efficient. Let’s take a look at the Truma Combi heating systems. These small, lightweight models get the job done while reducing energy consumption and protecting the environment.

About Truma

Philipp Kreis started Truma in Germany after World War II. He named it in honor of President Truman, who helped Germany rebuild with the Marshall Plan. The first RV heating system came out in 1961. For decades, Kreis and the team at Truma worked to build a top-quality company. 

Finally, in 1994, the first single appliance providing hot water and heat was introduced to the market. In the following years, Truma added air conditioning and water systems to its lineup. Today, Truma works with RV companies such as Airstream, DRV Luxury Suites, Forest River, Newmar, Winnebago, and others.

DRV Mobile Suites fifth wheel in snow
You can find Truma products in many well-known RV brands.

What Types of Systems Does Truma Manufacture? 

Truma is well-known in the RV industry. Many brands use Truma products, including the AquaGo water system, the Combi heating system, and the Aventa air conditioning system. They come standard on many newer RVs and are sometimes put in aftermarket.

Water Systems

The Truma water systems offer endless hot water for travelers. The Truma AquaGo comfort and the Truma AquaGo comfort plus both operate with hybrid technology for no scalding. Both models have an easy drain lever, an interior control panel switch, a clean mode for decalcification, and a comfort mode for winter camping. 

The Truma Combi also works as a water heating system. While it is not an on-demand water system, it uses a very small tank heated to a high temperature to provide hot water.

If you enjoy taking long hot showers as much as we do, you’ll understand Why We Love Our Truma AquaGo On-Demand Tankless RV Water Heater.

Truma AquaGo On-Demand RV Water Heater - Overview and Thoughts

Heating Systems

The Truma Combi and Truma VarioHeat come standard on many RVs straight from the manufacturer. There are four Truma Combi options and one Truma VarioHeat option. The near-silent operation and intelligent fan control mean you won’t have any problems getting to sleep or staying asleep. In addition, the Truma VarioHeat system can work in tandem with the Truma AquaGo system for a world-class hybrid system for heating and instant hot water.

Air Conditioning Systems

The Truma air conditioning systems include the Aventa eco and the Aventa comfort. The Aventa eco has a 13,500 BTU/h cooling capacity, while the Aventa comfort has a 15,000 BTU/h cooling capacity. Both have three modes (low, medium, and high) an automatic cooling mode, a dehumidifier mode, an air circulation mode, and a night mode.

Looking for An RV Air Conditioner That Is Both Efficient and Quiet? Look no further than the Truma Aventa!

Propane Systems

With the Truma LevelCheck, you can accurately determine how much propane is in your tank. It’s easy to use and suitable for all steel and aluminum LPG cylinders with diameters of 8inches to 14 inches. Never worry if you have enough propane to grill those chicken legs on the Blackstone or if you have enough propane to get through a cold winter night in Montana.

About the Truma Combi

The Truma Combi systems fall under the heating systems umbrella of the Truma brand. As already mentioned, the other system is the Truma VarioHeat, which is the most luxurious heating system available.

The pros of the Truma Combi systems are significant. First, the units are dual capable; they’re the RV’s water heater and furnace. This means they take up less space since they’re one appliance rather than two. It’s a big deal for smaller rigs like Class B vans and truck campers. Second, the units weigh 35 pounds to 37 pounds. When every pound matters in an RV, having a lightweight water heater and furnace matters. All of the units cost around $1,800.

A huge pro of the combi unit is how quite it is. The fan and burner are completely variable and will run at different speeds depending on the demand. You can use a low fan mode that most can bearly hear. Not loud cycling at night, just a quiet heat. The unit is also very efficient getting you more bang for your buck in propane.

The drawbacks to the combi, however, are that the furnace is not as powerful as other furnace options and the water tank is very small. This is offset by the very high temperature that the unit heats water too and can be a scalding concern. Once you get used to it we have found the units can produce enough water for one adequate shower, then it needs time to reheat.

truma combi on RV
The Truma combi is one of the most common furnace water heaters in Europe. Every time we have used one of these rvs it has had a combi unit.

Truma Combi eco

Capacity: 2.64 gallons (10L)

Fuel Type: Propane

Best Features: This heated water tank is ideal for cold wintry conditions. In summer mode, you can heat the water independently of the furnace. Four air outlets mean optimum warm air distribution. There are 7,500 BTU/h and 14,300 BTU/h operating levels.

Who It’s Best For: Smaller rigs like Class B vans and truck campers

Truma Combi eco plus

Capacity: 2.64 gallons (10L)

Fuel Type: Electric, propane, and mixed

Best Features: The Truma Combi eco plus uses very little energy at 850W. With the integrated heating elements, you can run the heater in gas mode for self-sufficient use, in electrical mode at the campsite, and mixed mode when outside temperatures are low. In the summer, when you don’t need the furnace, it will heat the water independently. Like the eco version, the eco plus has 7,500 BTU/h and 14,300 BTU/h operating levels.

Who It’s Best For: RVers who like to camp in colder climates

Truma Combi comfort plus

Capacity: 2.64 gallons (10L)

Fuel Type: Electric, propane, and mixed

Best Features: This model operates similarly to the eco plus model, but the comfort plus model has an additional operation level of 20,400 BTU/h. At campsites, you can run the heater with the 12V power supply unit instead of using the vehicle battery.

Who It’s Best For: Larger rigs from travel trailers to Class A motorhomes

Truma Combi D

Capacity: 2.64 gallons (10L)

Fuel Type: Electric, diesel, and mixed

Best Features: Like the Truma Combi comfort plus model, the Truma Combi D has three operating levels: 7,500 BTU/h, 14,300 BTU/h, and 20,400 BTU/h. The Truma Combi D gets up to 25% faster heating in mixed mode (diesel and electric) and is more efficient because of the reduced diesel combustion.

Who It’s Best For: RVers who like to camp in colder climates

TRUMA RV HEATING SYSTEM | How to Operate Your Truma Combi & Varioheat Systems In Your RV

Can You Winterize Your Truma Combi?

When your RV isn’t in use during the winter season, you must drain the Truma Combi’s water container. Once you drain it, the Combi furnace will have protection against freezing conditions that may damage the system. First, turn off the unit and let it cool down. Put a bucket underneath the Truma Combi to catch the released water.

Second, use the main switch or pump switch to turn off the power to the water pump. Open all the water release points at the faucets, showers, and toilets inside the RV. Make sure the Truma Combi is in bypass mode.

Then, flip the yellow handle up to drain the unit. Water will start pouring out of the drainage outlet of the drain valve. Leave the drain valve open for the winter season. Take the bucket of water with you before you leave.

Pro Tip: Avoid a time-consuming mess by learning How to Winterize Your RV with an Air Compressor (Without Messy Antifreeze).

Enjoy the Efficient and Effective Performance of a Truma Combi

If you’re looking to save space and lessen the weight load of your water heater and furnace, the Truma Combi options may be a good idea. You cant install these aftermarket in every RV, so it’s important to call Truma to speak with a customer service agent who can assist you. Truma does not sell the units directly to individuals to install DIY. Mobile technicians are available in Arizona, Texas, Florida, and Indiana to install new systems or repair existing ones.

Woman dressed for winter making a heart sign with her hands
Fall in love with winter RVing with a Truma Combi.

Will you be enjoying a cozy, warm RV interior because of a Truma Combi this winter? Drop a comment below.

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About Tom Morton

Tom, a Pacific Northwest native, is our technical genius. Born in Washington and raised in Alaska before settling in Michigan. He's the man who keeps our operation running, both figuratively and literally.

With a background in Electrical Engineering, Tom specializes in RV solar systems and lithium batteries. He made history as the first documented individual to use a Tesla battery module as an RV battery. Tom has personally assisted countless RVers with system installations and has educated thousands more through his videos and articles.

Cinematography is another of Tom's passions, showcased in his work on the Go North series. You can see his camera skills on display in The RVers TV show on Discovery Channel and PBS where he also stars as a co-host.

Tom's mechanical expertise extends beyond RVs to boats, planes, and all things mechanical. He's renowned for taking on maintenance and repair projects single-handedly and is often spotted underneath RVs, making him the technical backbone of our endeavors.

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ben zenize

Wednesday 1st of November 2023

i appreciate the info about the Truma Combi but there's one extremely important piece of information that you omitted from your article; you can't get one. Truma doesn't sell them to private parties and as far as i can see, there are no installers for that product either. if you have a secret source, please let me know. i got all excited about installing one of these in my van and realized i was wasting my time since they're not available.